Melt butter in a large stock pot over medium heat. Add onion and garlic and saute until soft and translucent.
Add flour and cook about 3-4 min until lightly browned.
Add the broth and bring to a boil, reduce heat and simmer 10 min to thicken, use a whisk to combine all the roux. Add chicken bouillon.
Add salsa, chicken, kidney beans, black beans, corn, fajita seasoning and cream of chicken soup and stir to combine.
Add milk and shredded cheese and cook until all the soup is combined and warmed through.
Garnish with parsley or cilantro, crushed tortilla chips, and more shredded cheese.